Benchmark: Compare prototype.reverse to for-loop

Script Preparation code:

var arr = [1, 2, 3, 4, 5, 6, 7, 8, 9, 0];

Tests:

Prototype.reverse()
return arr.reverse();
For-Loop
for(let i = 0; i < Math.floor(arr.length - 1); i++){ let temp = arr[i]; arr[i] = arr[arr.length - 1 - i]; arr[arr.length - 1 - i] = temp; } return arr;

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Prototype.reverse()
For-Loop

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/103.0.0.0 Safari/537.36

Browser/OS: Chrome 103 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Prototype.reverse()	8637524.0 Ops/sec
For-Loop	129135.4 Ops/sec

Autogenerated LLM Summary (model llama3.2:3b, generated 2 months ago):

LLMs can make mistakes. Check important info.

I'd be happy to explain the benchmark being tested.

**What is being tested?**

The provided JSON represents two individual test cases for comparing the performance of JavaScript arrays using the `reverse()` method (prototype-based) versus a traditional for-loop approach.

**Options compared:**

Two options are being compared:

1. **Prototype.reverse()**: This option uses the `reverse()` method on the array prototype, which is a built-in method that reverses the order of elements in an array.
2. **For-Loop**: This option uses a traditional for-loop to iterate over the array and swap its elements.

**Pros and Cons:**

**Prototype.reverse():**

Pros:

* More concise and readable code
* Built-in method, which means it's optimized by the JavaScript engine

Cons:

* May have overhead due to the need to create a new array object (although this is typically negligible)

**For-Loop:**

Pros:

* More control over the iteration process
* Can be more efficient for large arrays, as it avoids creating a new array object

Cons:

* More verbose and less readable code
* May have performance overhead due to the need to update multiple elements on each iteration

**Other considerations:**

Both options have their trade-offs. The `reverse()` method is often preferred for its conciseness and readability, but may incur some overhead. The for-loop approach provides more control over the iteration process but is typically less efficient.

**Library usage:**

None of the provided test cases uses any external libraries.

**Special JavaScript features or syntax:**

The provided code uses a few modern JavaScript features, such as:

* Arrow functions ( implicit `return` and `let` declarations)
* Template literals (the backtick `` character)

These features are supported by most modern JavaScript engines and are not specific to any particular library or framework.

**Alternative approaches:**

Other alternatives for reversing arrays include:

* Using the `splice()` method with negative indices
* Using the `map()` and `concat()` methods in combination
* Using a library like Lodash's `reverse()` function

However, these alternatives may have different performance characteristics and trade-offs compared to the two options being tested.

Related benchmarks:

Compare prototype.reverse to for-loop (version: 0)

Comparing prototype.reverse to for-loop

Comparing performance of: Prototype.reverse() vs For-Loop

Created: 2 years ago by: Guest

Jump to the latest result

Prototype.reverse()

For-Loop

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 2 months ago):